电感耦合等离子体原子发射光谱法测定银中8种杂质元素

采用硝酸-过氧化氢混合溶液分解样品,酒石酸防止锑、铋等元素水解,抗坏血酸还原后过滤并收集滤液。还原的银用硝酸-过氧化氢-酒石酸混合溶液分解,盐酸沉淀分离基体银以消除基体干扰,合并滤液,并在稀盐酸介质中,于电感耦合等离子体原子发射光谱仪(ICP-AES)上测定银中8种杂质元素(铜、铋、铁、铅、锑、钯、硒和碲)含量。通过试验,确定了适宜称样量为0.50~1.00 g。体系中残余银和共存其他杂质元素对测定结果无影响。使用不同方法对试验样品中铜、铋、铁、铅、锑、钯、硒和碲进行测定,测定结果与国标方法相符,相对标准偏差均小于5.0%。

Determination of eight elements in silver by inductively coupled plasma atomic emission spectrometry

The sample was decomposed using a mixed solution of nitric acid and hydrogen peroxide. The hydrolysis of antimony and bismuth was prevented with tartaric acid. After reduction with ascorbic acid, the solution was filtered and the filtration was collected. The reduced silver was decomposed again using nitric acid-hydrogen peroxide-tartaric acid mixed solution. Then, the matrix silver was precipitated and separated with hydrochloric acid to eliminate the matrix interference. The filtrate was merged. The content of eight impurity elements (copper, bismuth, iron, lead, antimony, palladium, selenium and tellurium) in silver was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) in diluted hydrochloric acid medium. The proper sampling weight (0.50-1.00 g) was obtained by experiments. The residual silver and other existence impurity elements in system had no influence on the determination results. The testing samples were determined using various methods. The determination results were consistent with those obtained by national standard methods. The relative standard deviations (RSD) for copper, bismuth, iron, lead, antimony, palladium, selenium and tellurium were all less than 5.0%.